Group B streptococcal infection

Last reviewed: 26 Aug 2022
Last updated: 07 May 2020



History and exam

Key diagnostic factors

  • fever
  • symptoms of meningitis
  • signs of meningitis
  • symptoms of sepsis
  • signs of sepsis
  • symptoms of pneumonia
  • signs of pneumonia
  • symptoms of UTI
  • signs of UTI
  • symptoms of cellulitis
  • signs of cellulitis
  • symptoms of septic arthritis
  • signs of septic arthritis
  • symptoms of conjunctivitis
  • symptoms of sinusitis
  • signs of sinusitis
  • symptoms of otitis media
  • signs of otitis media
  • symptoms of endometritis
  • signs of endometritis
  • signs of chorioamnionitis
More key diagnostic factors

Other diagnostic factors

  • nonspecific signs of infection in neonate
  • nonspecific signs of infection in older patients
  • symptoms of intra-abdominal infection
  • signs of intra-abdominal infection
  • midgestation abortion or preterm labor
Other diagnostic factors

Risk factors

  • 0 to 7 days of age
  • maternal fever during labor
  • premature rupture of membranes (PROM)
  • previous baby with GBS disease
  • maternal GBS colonization
  • GBS bacteriuria during pregnancy
  • preterm delivery (<37 weeks)
  • low birth weight (<2500 g)
  • deficient maternal-specific IgG at term
  • twin sibling with GBS disease
  • maternal age <20 years
  • chorioamnionitis
  • age >60 years
  • pregnancy
  • diabetes mellitus
  • advanced hepatic disease
  • advanced renal disease
  • presence of central venous catheter
  • urologic disorders
  • break in skin integrity or skin ulcers
  • neurologic disease
  • immunosuppression
  • nursing-home resident
  • black or Hispanic race
  • malignancy
  • primiparity
  • obstetric manipulation
  • presence of urinary catheter
  • HIV infection
  • trauma
  • asthma
  • consumption of placenta capsules
More risk factors

Diagnostic investigations

1st investigations to order

  • CBC
  • BUN
  • serum electrolytes
  • serum glucose
  • coagulation studies
  • LFTs
  • C-reactive protein (CRP)
  • blood culture
  • cerebrospinal fluid (CSF) Gram stain
  • CSF culture
  • CSF cell count and differential
  • CSF glucose and protein
  • antigen detection in CSF
  • Gram stain and culture of other sterile body fluids
  • chest x-ray
  • joint x-ray
  • CT head
More 1st investigations to order

Investigations to consider

  • echocardiography
More investigations to consider

Treatment algorithm


early- or late-onset neonatal infection (0-89 days of age)

infants and children




Brendan Healy, MBChB, BSc (Hons), MRCP, FRCPath

Consultant in Microbiology and Infectious Diseases

University Hospital of Wales




BH has received educational grants and fees for consultancy from a number of pharmaceutical companies, including BMS, Gilead, Jannsenn, Abbvie, ViiV, and MSD. This is principally in work relating to hepatitis C and HIV. BH has carried out consultancy work on some antibiotics, including fidaxomicin, linezolid, tedizolid, ceftobiprole, and ceftaroline. BH declares he has no competing interests in relation to the work carried out for this topic review, Group B streptococcus.


Dr Brendan Healy would like to gratefully acknowledge Dr Susannah Froude and Dr Harriet Hughes, previous contributors to this topic.


SF declares that she has no competing interests. HH declares that she has received funds from Gilead and Biocomposites related to conference registration, travel, accommodation, and speaker fees.

Peer reviewers

William A. Petri, Jr, MD, PhD, FACP

Chief and Professor of Medicine

Division of Infectious Diseases and International Health

University of Virginia Health System




WAP declares that he has no competing interests.

James R. Hanley, MD, FAAP

Assistant Professor


Attending Physician

Pediatric Emergency Medicine

University of Southern Alabama Children's and Women's Hospital




JRH declares that he has no competing interests.

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